The reserve has an area of 163.6 square kilometres (63.2 sq mi) and includes many mountain peaks measuring over 1,200 metres above sea level, the tallest being Daecheongbong, at an altitude of 1,708 metres (5,604 ft). The ranges are composed largely of dissected granite and gneiss. The annual precipitation is about 1,000 millimetres in Inner Soraksan and 1,300 millimetres in Outer Soraksan.[2]